Field of Invention
The present disclosure relates to a light emitting apparatus for a vehicle. More particularly, it relates to a light emitting apparatus for a vehicle that diffuses the light from a light source and produces a more evenly or uniformly distributed light.
Background Art
Recently, a variety of researches and changes are made about the illumination apparatus for a vehicle. The changes are made not only about the exterior design of the lamp but also about the entire lamp including the interior reflector. These changes include the variations of the light emitting apparatus of the lamp, that is, according to a related art, a light generation method using a simple electric bulb is used, however, recently, light emitting apparatuses using a variety of light sources such as the laser, LED or the like are being developed. In case of the laser among these, since the high density energy can be generated so that there is an advantage of capable of irradiating a comparatively far distance, the development is more vigorously performed.
In general, in case of using only one laser, the amount of light is insufficient, so plural lasers are used and lights are superimposed. However, in this case, there occurs a collection of the light of the laser and thus there arises a problem in that the energy is not uniformly distributed.
Specifically describing this by referring to FIGS. 1A and 1B which are views illustrating a conventional light emitting apparatus using a laser, where FIG. 1A is a view illustrating the energy distributions with each laser, and FIG. 1B is a view illustrating a superimposed shape of lasers and an energy distribution thereof. Since the laser diode, due to the property of the laser, forms a beam pattern in a form of an elliptic shape in which the energy is concentrated more at the center and irradiates light when using three or plural laser diodes, the light is superimposed only on the center as shown in FIG. 1B. This means that the energy is collected on the center and is not uniformly distributed over an entire irradiation area of the beam pattern as shown in the graphs. If the energy is not uniformly distributed, then the inefficiency in using the energy is caused, and the degradation of the fluorescent body which changes the wavelength of the laser is accelerated, and further it even causes a problem of inducing the functional damage or destruction of the fluorescent body. Therefore, a light emitting apparatus is required in which a plurality of light sources form a superimposition of the beam patterns matching each other.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.